Heat exchange unit



April 5, 1955 B. F. wATsoN HEAT EXCHANGE UNIT 2 Sheets-Sheet 2 Filed July l2, 1952 United States Patent O HEAT EXCHANGE UNIT Bradley F. Watson, Dayton, Ohio, assignor to General Motors Corporation, Dayton, Ohio, a corporation of Delaware Application July 12, 1952, Serial No. 298,542

4 Claims. (Cl. 257-154) This invention relates to a domestic appliance and more particularly to heat transfer units.

Heat transfer units are made in a variety of configurations. Some require elaborate machinery and processes.

It is an object of my invention to provide a simple heat transfer unit which may be readily manufactured with simple machinery at a low cost.

It is another object of my invention to provide a simple heat transfer unit which has high efficiency and which allows the free quiet ilow of two heat transfer fluids in separating relationship and which may be readily cleaned in ilowing water.

These objects are attained in the form shown by providing spaced perforated sheets between which extends a plurality of spaced parallel multiple tubular units. Each unit is made up of two halves, each having complementary semicylindrical portions connected by webs. The two parts are fastened together at the webs and at each end to form a completed structure in which there are provided parallel tubes registering with the perforation in the sheets.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein a preferred form of the invention is clearly shown.

ln the drawings:

Figure l is a top view of a heat transfer unit illustrating one form of my invention;

Figure 2 is a front view of the heat transfer unit shown in Figure l;

Figure 3 is a sectional view taken substantially along the line 3 3 of Figure l;

Figure 4 is a sectional view of one element of one of the tubular assemblies taken along the line 4 4 of Figure 3; and

Figure 5 is a sectional view of the complementary element of the tubular assembly also taken along the line 4 4 of Figure 3.

Referring now to the drawings and more particularly to Figures 1 to 3, there is shown a top sheet 20 and a bottom sheet 22. Each of these sheets have aligned rows of six holes or perforations with alternate rows staggered as shown in Figure 1. At the opposite rear and front edges, the top sheet is provided with the flanged beads 24 and 26 while the bottom sheet 22 is provided with the flanged beads 28 and 30.

Extending between the sheets 2l) and 22 and aligned with the rows of holes are the tubular assemblies, one of which is indicated by the reference character 32 and shown in section in Figure 3. In Figures 4 and 5 this tubular assembly 32 is shown in an exploded arrangement in which the one part or element 34 is shown in Figure 4 provided with six semicylindrical sections 36 which are joined together by intervening webs 38. The element 40 which is shown in Figure 5 has six complementary semicylindrical sections 42 likewise joined together by webs 44 which are equal in size to the webs 38. The element 34 at its opposite ends is provided with lips 46.

These two elements 34 and 40 are assembled together with the webs 38 and 44 in contact with each other. The lips 46 are folded over the ends 48 of the element 40 as illustrated in Figures 2 and 3. The element 34 has eyelets 52 extruded in the webs 38 in the direction away from the semicylindrical sections 36. The element 40 has apertures pierced in its webs 44 of a size just large enough to receive the eyelets 52 when the two elements 34 and 40 are assembled together. The eylets extend ICC through the pierced holes in the webs l44 of the element 40 and the projecting ends of the eyelets 52 are spun over to rivet the webs 44 and 38 together. This provides a unit in which there are six spaced parallel tubular sections connected by webs.

The ends of the webs 38 and 44 are made shorter than the ends of the semicylindrical sections 38 and 42 so that the ends of the semicylindrical sections may extend through the holes or apertures 54 and `56 in the top and bottom sheets 20 and 22. The ends of the semicylindrical sections 36 and 42 are spun over as illustrated by the reference characters 58 and 60 to join the top and bottom sheets 20 and 22 to each of the tubular assemblies and to seal the interior of the tubes from the space surrounding the tubes. All of the tubular assemblies are identical and all are joined to the top and bottom sheets by flaring and flattening the protruding ends or by spinning over the protruding ends of the cylindrical sections as shown. The webs serve as spacers to keep the sheets 20 and 22 uniformly spaced.

The top and bottom plates of one end are connected to a front panel 62. This front panel together with the beads 24, 26, 28, and 30 makes the assembly rigid so that it will retain its shape even though thin gage sheets are used. The tubes provide a free flow of fluidfrom the space above the top sheet to the space below the bottom sheet while the spaces between the tubular assemblies between the top and bottom sheets 20 and 22 provide a free flow of fluid surrounding the tubular assemblies. The tortuous path provided by the staggered arrangement insures that the outer surface of the tubes are continuously wiped by the fluid so that good heat transfer efficiency can be obtained. The webs increase the surface area of contact of one fluid.

While the form of embodiment of the invention as herein disclosed constitutes a preferred form, it is to be understood that other forms might be adopted as may come within the scope of the claims which follow.

What is claimed is as follows:

1. A heat transfer unit including a first sheet metal element in the form of a plurality of spaced sections of tubes joined together by webs which are shorter than the sections of the tubes in their axial directions, a second sheet metal element in the form of a plurality of spaced sections of tubes joined together by webs which are shorter than the sections of tubes in their axial directions, the web portions of said rst element being in abutting contact with the web portions of said second element, a set of perforated plates extending transversely to the axes of said tubular sections spaced by and in contact with said webs, the ends of said tubular sections extending into and contacting the inner periphery of the perforations in said plates and being provided with means for holding said plates in contact with the ends of said webs.

2. A heat transfer unit including two spaced perforated sheets, a rst element having a plurality of spaced semicylindrical sections connected by webs which are shorter than the semi-cylindrical sections in their axial directions, a second element having a plurality of spaced semicylindrical sections connected by webs which are shorter than the semi-cylindrical sections in their axial directions,

the first and second elements being joined together with their webs in abutting relationship to form spaced cylindrical tubes, the upper and lower ends of said sections extending into and contacting the inner periphery of the perforations in said sheets, said webs extending into contact with said sheets to serve as a spacing means to keep the sheets a uniform distance apart, the ends of said cylindrical tube sections being provided with means for holding the said plates in contact with the ends of said webs.

3. A heat transfer unit including two spaced perforated sheets, a first element having a plurality of spaced semicylindrical sections connected by webs which are shorter than the semi-cylindrical sections in their axial directions, a second element having a plurality of spaced semi-cylindrical sections connected by webs which are shorter than the semi-cylindrical sections in their axial directions, the first and second elements being joined together with their webs in abutting relationship to form spaced cylindrical tubes, the upper and lower ends of said sections extending into and contacting the inner periphery of the perforations in said sheets, said webs extending into contact with said sheets to serve as a spacing means to keep the sheets a uniform distance apart, the ends of said cylindrical tube sections overlapping the edges of said perforatons for holbding the said plates in contact with the ends of said we s.

4. A heat transfer unit including a iirst sheet metal element in the form of a plurality of spaced sections of tubes joined together by webs which are shorter than the sections of the tubes in their axial directions, a second sheet metal element in the form of a plurality of spaced sections of tubes joined together by webs which are shorter than the sections of tubes in their axial directions, the web portions of said first element being in abutting contact with the web portions of said second element, a set of perforated plates extending transversely to the axes of said tubular sections spaced by and in' contact with said webs, the ends of said tubular sections extending into and site edges of said plates generally transverse to said webs lbeing provided with stifening beads.

References Cited in the file of this patent UNITED STATES PATENTS 1,320,652 Sonneborn Nov. 4, 1919 2,272,863 Young Feb. 10, 1942 FOREIGN PATENTS 139,585 Switzerland July 1, 1930 297,149 Italy June 6, 1932 371,605 Great Britain Apr. 28, 1932 909,811 France Jan. 7, 1946 

